Military vehicle

ABSTRACT

A military vehicle includes a brake positioned to facilitate braking a tractive element, a brake housing defining an inner volume, a piston separating the inner volume into a first chamber and a second chamber, a rod extending through an end of the brake housing and coupled to the piston where the rod is positioned to selectively engage with the brake to inhibit movement of the tractive element, a resilient member positioned within the inner volume and configured to generate a biasing force against the piston such that the rod is biased into engagement with the brake, and an air-to-hydraulic intensifier coupled to the brake housing. The air-to-hydraulic intensifier is configured to receive a supply of air and provide a hydraulic fluid to the brake housing based on the supply of air to overcome the biasing force to disengage the rod from the brake to permit movement of the tractive element.

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/529,508, filed Aug. 1, 2019, which is a continuation of U.S. patentapplication Ser. No. 15/599,174, filed May 18, 2017, which is acontinuation of U.S. patent application Ser. No. 14/724,279, filed May28, 2015, which is a continuation of U.S. patent application Ser. No.13/841,686, filed Mar. 15, 2013, which claims the benefit of U.S.Provisional Patent Application No. 61/615,812, filed Mar. 26, 2012, allof which are incorporated herein by reference in their entireties.

BACKGROUND

The present application relates to vehicles. In particular, the presentapplication relates to the structural frame assembly of a militaryvehicle.

A military vehicle may be used in a variety of applications andconditions. These vehicles generally include a number of vehicle systemsor components (e.g., a cab or body, a drive train, etc.). The militaryvehicle may also include various features and systems as needed for thespecific application of the vehicle (e.g., a hatch, a gun ring, anantenna, etc.). Proper functioning and arrangement of the vehiclesystems or components is important for the proper functioning of thevehicle.

Traditional military vehicles include a cab assembly coupled to a pairof frame rails that extend along the length of the vehicle. The drivetrain, engine, and other components of the vehicle are coupled to theframe rails. Such vehicles may be transported by securing lifting slingsto the frame rails and applying a lifting force (e.g., with a crane,with a helicopter, etc.). As the frame rails are the primary structureof the vehicle, a lifting force applied to a rear portion and a frontportion elevate the vehicle from a ground surface. In such aconfiguration, the components of the vehicle must be coupled to thestructural frame rails thereby requiring sequential assembly.

SUMMARY

One embodiment relates to a military vehicle. The military vehicleincludes a chassis, an axle coupled to the chassis, a tractive elementcoupled to the axle, a brake positioned to facilitate braking thetractive element, a brake housing defining an inner volume, a pistonseparating the inner volume into a first chamber and a second chamber, arod extending through an end of the brake housing and coupled to thepiston where the rod is positioned to selectively engage with the braketo inhibit movement of the tractive element, a resilient memberpositioned within the inner volume and configured to generate a biasingforce against the piston such that the rod is biased into engagementwith the brake, and an air-to-hydraulic intensifier coupled to the brakehousing. The air-to-hydraulic intensifier is configured to receive asupply of air and provide a hydraulic fluid to the brake housing basedon the supply of air to overcome the biasing force to disengage the rodfrom the brake to permit movement of the tractive element.

Another embodiment relates to a brake system. The brake system includesa brake configured to facilitate braking a tractive element, a brakehousing defining an inner volume, a piston separating the inner volumeinto a first chamber and a second chamber, a rod extending through anend of the brake housing and coupled to the piston where the rod ispositioned to selectively engage with the brake to inhibit movement ofthe tractive element, a resilient member positioned within the innervolume and configured to generate a brake biasing force against thepiston such that the rod is biased into engagement with the brake, andan air-to-hydraulic intensifier coupled to the brake housing. Theair-to-hydraulic intensifier is configured to receive a supply of airand provide a hydraulic fluid to the brake housing based on the supplyof air to overcome the brake biasing force to disengage the rod from thebrake to permit movement of the tractive element.

Still another embodiment relates to a military vehicle. The militaryvehicle includes a brake configured to facilitate braking a tractiveelement, a brake housing defining an inner volume, a piston separatingthe inner volume into a first chamber and a second chamber, a rodextending through an end of the brake housing and coupled to the pistonwhere the rod is positioned to selectively engage with the brake toinhibit movement of the tractive element, a resilient member positionedwithin the inner volume and configured to generate a brake biasing forceagainst the piston to bias the rod into engagement with the brake, ahydraulic reservoir, an air-to-hydraulic intensifier coupled to thebrake housing, a valve, and an air supply line. The air-to-hydraulicintensifier is configured to receive a supply of air and provide ahydraulic fluid to the brake housing based on the supply of air toovercome the brake biasing force to disengage the rod from the brake topermit movement of the tractive element. The valve includes a first portfluidly coupled to the air-to-hydraulic intensifier, a second portfluidly coupled to the hydraulic reservoir, a third port fluidly coupledto the brake housing, a valve gate, an air pilot, and a biasing element.The valve gate is repositionable between a first position and a secondposition. The first position couples the first port to the third port tofluidly couple the air-to-hydraulic intensifier to the brake housing.The second position couples the second port to the third port to fluidlycouple the hydraulic reservoir to the brake housing. The biasing elementis configured to provide a valve biasing force to the valve gate to biasthe valve gate into the second position. The air supply line isconfigured to provide the supply of air to the air-to-hydraulicintensifier and the air pilot. The brake biasing force of the resilientmember is configured to bias the piston to force the hydraulic fluid outof the brake housing, through the valve, and into the hydraulicreservoir in response to the valve being in the second position.

The invention is capable of other embodiments and of being carried outin various ways. Alternative exemplary embodiments relate to otherfeatures and combinations of features as may be recited in the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure will become more fully understood from the followingdetailed description, taken in conjunction with the accompanyingfigures, wherein like reference numerals refer to like elements, inwhich:

FIGS. 1-2 are a perspective views of a vehicle, according to anexemplary embodiment.

FIG. 3 is a schematic side view of the vehicle of FIG. 1, according toan exemplary embodiment.

FIGS. 4-6 are perspective views of a vehicle having a passenger capsule,a front module, and a rear module, according to an exemplary embodiment.

FIGS. 7-9 are perspective views of a vehicle having a passenger capsule,a front module, and a rear module, according to an alternativeembodiment.

FIG. 10A is a schematic sectional view of a vehicle having at least aportion of a suspension system coupled to a transaxle, according to anexemplary embodiment, and FIG. 10B is schematic sectional view of avehicle having a passenger capsule, according to an exemplaryembodiment.

FIG. 11 is schematic view of a braking system for a vehicle, accordingto an exemplary embodiment.

FIG. 12 is schematic view of a vehicle control system, according to anexemplary embodiment.

DETAILED DESCRIPTION

Before turning to the figures, which illustrate the exemplaryembodiments in detail, it should be understood that the presentapplication is not limited to the details or methodology set forth inthe description or illustrated in the figures. It should also beunderstood that the terminology is for the purpose of description onlyand should not be regarded as limiting.

Referring to FIGS. 1-3, a military vehicle 1000 includes a hull andframe assembly 100, an armor assembly 200, an engine 300, a transmission400, a transaxle 450, wheel and tire assemblies 600, a braking system700, a fuel system 800, and a suspension system 460 coupling the hulland frame assembly 100 to the wheel and tire assemblies 600. Accordingto an exemplary embodiment, the military vehicle 1000 includes a powergeneration system 900. As shown in FIG. 1, the military vehicle 1000also includes a trailer 1100.

Hull and Frame Assembly

Referring to FIG. 2, the hull and frame assembly 100 includes apassenger capsule, shown as passenger capsule 110, a front module, shownas front module 120, and a rear module, shown as rear module 130.According to an exemplary embodiment, the front module 120 and the rearmodule 130 are coupled to the passenger capsule 110 with a plurality ofinterfaces. As shown in FIG. 2, the front module 120 includes a frontaxle having wheel and tire assemblies 600.

According to an exemplary embodiment, the rear module 130 includes abody assembly, shown as bed 132. As shown in FIG. 2, front module 120also includes a body panel, shown as hood 122. In some embodiments, thehood 122 partially surrounds the engine of military vehicle 1000. Thehood 122 is constructed of a composite material (e.g., carbon fiber,fiberglass, a combination of fiberglass and carbon fiber, etc.) andsculpted to maximize vision and clear under-hood components. Accordingto an alternative embodiment, the hood 122 is manufactured from anothermaterial (e.g., steel, aluminum, etc.). The front portion of hood 122mounts to a lower cooling package frame, and the upper mount rests onthe windshield wiper cowl. This mounting configuration reduces thenumber and weight of components needed to mount the hood 122. TheOshkosh Corporation® logo is mounted to a frame structure, which isitself mounted directly to the cooling package. The hood 122 includesbumperettes 123 that provide mounting locations for antennas (e.g., aforward-facing IED jammer, a communications whip antenna, etc.). In oneembodiment, the bumperettes 123 and front of the hood 122 may bereinforced (e.g., with structural fibers, structural frame members,etc.) to become structural members intended to prevent damage to thetire assemblies 600. In an alternative embodiment, the bumperettes 123may be crushable members or “break away” members that disengage uponimpact to prevent interference between the bumperettes 123 and tireassemblies 600 in the event of a front impact.

Referring next to the exemplary embodiment shown in FIGS. 4-9, themilitary vehicle 1000 includes passenger capsule 110, front module 120,and rear module 130. As shown in FIGS. 4 and 7, passenger capsule 110includes a structural shell 112 that forms a monocoque hull structure.Monocoque refers to a form of vehicle construction in which the vehiclebody and chassis form a single unit. The structural shell 112 isconfigured to provide a structural load path between front module 120and rear module 130 of military vehicle 1000 (e.g., during driving, alifting operation, during a blast event, etc.). According to anexemplary embodiment, the structural shell 112 includes a plurality ofintegrated armor mounting points configured to engage a supplementalarmor kit (e.g., a “B-Kit,” etc.). The structural shell 112 is rigidlyconnected to the rest of the powertrain, drivetrain, suspension, andmajor systems such that they all absorb blast energy during a blastevent, according to an exemplary embodiment. According to an exemplaryembodiment, the structural shell 112 is large enough to containfour-passengers in a standard two-by-two seating arrangement and fourdoors 104 are rotatably mounted to the structural shell 112. Accordingto the alternative embodiment shown in FIGS. 7-9, two doors 104 arecoupled to structural shell 112. Front module 120 and rear module 130are configured to engage a passenger capsule having either two doors orfour doors, according to an exemplary embodiment. As shown in FIGS. 6and 9, the structural shell 112 includes a first end 114 and a secondend 116.

According to an exemplary embodiment, front module 120 includes asubframe having a first longitudinal frame member 124 and a secondlongitudinal frame member 126. As shown in FIGS. 4-9, an underbodysupport structure 128 is coupled to the first longitudinal frame member124 and the second longitudinal frame member 126. According to anexemplary embodiment, the first longitudinal frame member 124 and thesecond longitudinal frame member 126 extend within a common plane (e.g.,a plane parallel to a ground surface). The underbody support structure128 is coupled to the first end 114 of structural shell 112 and includesa plurality of apertures 129 that form tie down points. In someembodiments, an engine for the military vehicle 1000 is coupled to thefirst longitudinal frame member 124 and the second longitudinal framemember 126. In other embodiments, the front module 120 includes a frontaxle assembly coupled to the first longitudinal frame member 124 and thesecond longitudinal frame member 126.

As shown in FIGS. 4 and 6, rear module 130 includes a subframe having afirst longitudinal frame member 134 and a second longitudinal framemember 136. As shown in FIGS. 4-9, an underbody support structure 138 iscoupled to the first longitudinal frame member 134 and the secondlongitudinal frame member 136. According to an exemplary embodiment, thefirst longitudinal frame member 134 and the second longitudinal framemember 136 extend within a common plane (e.g., a plane parallel to aground surface). The underbody support structure 138 is coupled to thesecond end 116 of structural shell 112, the first longitudinal framemember 134, and the second longitudinal frame member 136. According toan exemplary embodiment, the first longitudinal frame member 134 and thesecond longitudinal frame member 136 include a plurality of apertures139 that form tie down points. In some embodiments, a transaxle 450 or adifferential for the military vehicle 1000 is coupled to at least one ofthe first longitudinal frame member 134 and the second longitudinalframe member 136. In other embodiments, the rear module 130 includes arear axle assembly coupled to the first longitudinal frame member 134and the second longitudinal frame member 136.

The subframes of the front module 120 and the rear module 130 may bemanufactured from High Strength Steels (HSS), high strength aluminum, oranother suitable material. According to an exemplary embodiment, thesubframes feature a tabbed, laser cut, bent and welded design. In otherembodiments, the subframes may be manufactured from tubular members toform a space frame. The subframe may also include forged, rather thanfabricated or cast frame sections to mitigate the stress, strains, andimpact loading imparted during operation of military vehicle 1000.Aluminum castings may be used for various cross member components wherethe loading is compatible with material properties. Low cost aluminumextrusions may be used to tie and box structures together.

The structural shell 112 and the subframes of the front module 120 andthe rear module 130 are integrated into the hull and frame assembly 100to efficiently carry chassis loading imparted during operation of themilitary vehicle 1000, during a lift event, during a blast event, orunder still other conditions. During a blast event, conventional framerails can capture the blast force transferring it into the vehicle.Military vehicle 1000 replaces conventional frame rails and insteadincludes passenger capsule 110, front module 120, and rear module 130.The passenger capsule 110, front module 120, and rear module 130provides a vent for the blast gases (e.g., traveling upward after thetire triggers an IED) thereby reducing the blast force on the structuralshell 112 and the occupants within passenger capsule 110. Traditionalframe rails may also directly impact (i.e. contact, engage, hit, etc.)the floor of traditional military vehicles. Military vehicle 1000 thatincludes passenger capsule 110, front module 120, and rear module 130does not include traditional frame rails extending along the vehicle'slength thereby eliminating the ability for such frame rails to impactthe floor of the passenger compartment. Military vehicle 1000 thatincludes a passenger capsule 110, front module 120, and rear module 130also has an improved strength-to-weight performance, abuse tolerance,and life-cycle durability.

According to an exemplary embodiment, the doors 104 incorporate a combatlock mechanism. In some embodiments, the combat lock mechanism iscontrolled through the same handle that operates the automotive doorlatch system, allowing a passenger to release the combat locks andautomotive latches in a single motion for quick egress. The doors 104also interface with an interlocking door frame 109 defined withinstructural shell 112 adjacent to the latch, which helps to keep thedoors 104 closed and in place during a blast even. Such an arrangementalso distributes blast forces between a front and a rear door mountingand latching mechanism thereby improving door functionality after ablast event.

Lift Structure

According to an exemplary embodiment, the military vehicle 1000 may betransported from one location to another in an elevated position withrespect to a ground surface (e.g., during a helicopter lift operation,for loading onto or off a ship, etc.). As shown in FIGS. 4-9, militaryvehicle 1000 includes a lift structure 140 coupled to the front module120. According to an exemplary embodiment, the lift structure includes afirst protrusion 144 extending from the first longitudinal frame member124, a second protrusion 146 coupled to the second longitudinal framemember 126, and a lateral frame member 148 extending between the firstprotrusion 144 and the second protrusion 146. As shown in FIGS. 4-9, thefirst protrusion 144 and the second protrusion 146 extend along an axisthat is generally orthogonal (e.g., within 20 degrees of an orthogonalline) to a common plane within which the first longitudinal frame member134 and the second longitudinal frame member 126 extend. As shown inFIGS. 5-6 and 8-9, the first protrusion 144 defines a first aperture145, and the second protrusion 146 defines a second aperture 147. Thefirst aperture 145 and the second aperture 147 define a pair of frontlift points. An operator may engage the front lift points with a sling,cable, or other device to elevate military vehicle 1000 from a groundsurface (e.g., for transport).

According to an exemplary embodiment, the hood 122 defines an outersurface (e.g., the surface exposed to a surrounding environment) and aninner surface (e.g., the surface facing the first longitudinal framemember 124 and the second longitudinal frame member 126). It should beunderstood that the outer surface is separated from the inner surface bya thickness of the hood 122. As shown schematically in FIGS. 4, 6-7, and9, first protrusion 144 and second protrusion 146 extend through a firstopening and a second opening defined within the hood 122. According toan exemplary embodiment, the pair of front lift points is positionedalong the outer surface of the hood 122 (e.g., to provide preferredsling angles, to facilitate operator access, etc.).

According to an exemplary embodiment, the first longitudinal framemember 124 and the second longitudinal frame member 126 are coupled tothe first end 114 of the structural shell 112 with a plurality ofinterfaces. Such interfaces may include, by way of example, a pluralityof fasteners (e.g., bolts, rivets, etc.) extending through correspondingpads coupled to the front module 120 and the structural shell 112.According to an exemplary embodiment, a lifting force applied to thepair of front lift points is transmitted into the structural shell ofthe passenger capsule to lift the vehicle.

In some embodiments, the military vehicle 1000 includes breakawaysections designed to absorb blast energy and separate from the remainingcomponents of military vehicle 1000. The blast energy is partiallyconverted into kinetic energy as the breakaway sections travel from theremainder of military vehicle 1000 thereby reducing the total energytransferred to the passengers of military vehicle 1000. According to anexemplary embodiment, at least one of the front module 120 and the rearmodule 130 are breakaway sections. Such a military vehicle 1000 includesa plurality of interfaces coupling the front module 120 and the rearmodule 130 to passenger capsule 110 that are designed to strategicallyfail during a blast event. By way of example, at least one of theplurality of interfaces may include a bolted connection having aspecified number of bolts that are sized and positioned (e.g., five 0.5inch bolts arranged in a pentagon, etc.) to fail as an impulse force isimparted on front module 120 or rear module 130 during a blast event. Inother embodiments, other components of the military vehicle 1000 (e.g.,wheel, tire, engine, etc.) are breakaway sections.

Referring again to the exemplary embodiment shown in FIGS. 4-6, themilitary vehicle 1000 may be lifted by a pair of apertures definedwithin a pair of protrusions 115. The apertures define a pair of rearlift points for military vehicle 1000. As shown in FIG. 5, the pair ofprotrusions 115 extend from opposing lateral sides of the structuralshell 112. It should be understood that a lifting force applied directlyto the pair of protrusions 115 may, along with the lifting force appliedto lift structure 140, elevate the military vehicle 1000 from a groundsurface. The structural shell 112 carries the loading imparted by thelifting forces applied to the lift structure 140 (e.g., through theplurality of interfaces) and the pair of protrusions 115 to elevate themilitary vehicle 1000 from the ground surface without damaging thepassenger capsule 110, the front module 120, or the rear module 130.

Armor Assembly

Referring next to the exemplary embodiment shown in FIG. 10B, the armorassembly 200 includes fabricated subassemblies (roof, floor, sidewalls,etc.) that are bolted together. The armor assembly 200 may bemanufactured from steel or another material. The armor assembly 200provides a robust and consistent level of protection by using overlapsto provide further protection at the door interfaces, componentintegration seams, and panel joints.

In another embodiment, the armor assembly 200 further includes a360-degree modular protection system that uses high hard steel,commercially available aluminum alloys, ceramic-based SMART armor, andtwo levels of underbody mine/improved explosive device (“IED”)protection. The modular protection system provides protection againstkinetic energy projectiles and fragmentation produced by IEDs andoverhead artillery fire. The modular protection system includes twolevels of underbody protection. The two levels of underbody protectionmay be made of an aluminum alloy configured to provide an optimumcombination of yield strength and material elongation. Each protectionlevel uses an optimized thickness of this aluminum alloy to defeatunderbody mine and IED threats.

Referring now to FIG. 10B, the armor assembly 200 also includes apassenger capsule assembly 202. The passenger capsule assembly 202includes a V-shaped belly deflector 203, a wheel deflector, a floatingfloor, footpads 206 and energy absorbing seats 207. The V-shaped bellydeflector 203 is integrated into the sidewall. The V-shaped bellydeflector 203 is configured to mitigate and spread blast forces along abelly. In addition, the wheel deflector mitigates and spreads blastforces. The “floating” floor utilizes isolators and standoffs todecouple forces experienced in a blast event from traveling on a directload path to the passenger's lower limbs. The floating floor mounts topassenger capsule assembly 202 isolating the passenger's feet fromdirect contact with the blast forces on the belly. Moreover, footpadsprotect the passenger's feet. The energy absorbing seats 207 reduceshock forces to the occupants' hips and spine through a shock/springattenuating system. The modular approach of the passenger capsuleassembly 202 provides increased protection with the application ofperimeter, roof and underbody add on panels. The components of thepassenger capsule assembly 202 mitigate and attenuate blast effects,allow for upgrades, and facilitate maintenance and replacements.

The passenger capsule assembly 202 further includes a structural tunnel210. For load purposes, the structural tunnel 210 replaces a frame orrail. The structural tunnel 210 has an arcuately shaped cross sectionand is positioned between the energy absorbing seats 207. Theconfiguration of the structural tunnel 210 increases the distancebetween the ground and the passenger compartment of passenger capsuleassembly 202. Therefore, the structural tunnel 210 provides greaterblast protection from IEDs located on the ground because the IED has totravel a greater distance in order to penetrate the structural tunnel210.

Engine

The engine 300 is a commercially available internal combustion enginemodified for use on military vehicle 1000. The engine 300 includes aVariable Geometry Turbocharger (VGT) configured to reduce turbo lag andimprove efficiency throughout the engine 300's operating range byvarying compressor housing geometry to match airflow. The VGT also actsas an integrated exhaust brake system to increase engine brakingcapability. The VGT improves fuel efficiency at low and high speeds andreduces turbo lag for a quicker powertrain response.

The engine 300 includes a glow plug module configured to improve theengine 300 cold start performance. In some embodiments, no etherstarting aid or arctic heater is required. The glow plug module createsa significant system cost and weight reduction.

In addition, engine 300 includes a custom oil sump pickup and windagetray, which ensures constant oil supply to engine components. Theintegration of a front engine mount into a front differential gear boxeliminates extra brackets, reduces weight, and improves packaging.Engine 300 may drive an alternator/generator, a hydraulic pump, a fan,an air compressor and/or an air conditioning pump. Engine 300 includes atop-mounted alternator/generator mount in an upper section of the enginecompartment that allows for easy access to maintain thealternator/generator and forward compatibility to upgrade to ahigher-power export power system. A cooling package assembly is providedto counteract extreme environmental conditions and load cases.

According to an exemplary embodiment, the military vehicle 1000 alsoincludes a front engine accessory drive (FEAD) that mounts engineaccessories and transfers power from a front crankshaft dampener/pulleyto the accessory components through a multiple belt drive system.According to an exemplary embodiment, the FEAD drives a fan, analternator, an air conditioning pump, an air compressor, and a hydraulicpump. There are three individual belt groups driving these accessoriesto balance the operational loads on the belt as well as driving them atthe required speeds. A top-mounted alternator provides increased accessfor service and upgradeability when switching to the export power kit(e.g., an alternator, a generator, etc.). The alternator is mounted tothe front sub frame via tuned isolators, and driven through a constantvelocity (CV) shaft coupled to a primary plate of the FEAD. This isdriven on a primary belt loop, which is the most inboard belt to thecrank dampener. No other components are driven on this loop. A secondarybelt loop drives the hydraulic pump and drive through pulley. This loophas one dynamic tensioner and is the furthest outboard belt on thecrankshaft dampener pulley. This belt loop drives power to a tertiarybelt loop through the drive through pulley. The tertiary belt loopdrives the air conditioning pump, air compressor, and fan clutch. Thereis a single dynamic tensioner on this loop, which is the furthestoutboard loop of the system.

Transmission, Transfer Case, Differentials

Military vehicle 1000 includes a commercially available transmission400. Transmission 400 also includes a torque converter configured toimprove efficiency and decrease heat loads. Lower transmission gearratios combined with a low range of an integrated reardifferential/transfer case provide optimal speed for slower speeds,while higher transmission gear ratios deliver convoy-speed fuel economyand speed on grade. In addition, a partial throttle shift performancemay be refined and optimized in order to match the power outputs of theengine 300 and to ensure the availability of full power with minimaldelay from operator input. This feature makes the military vehicle 1000respond more like a high performance pickup truck than a heavy-dutyarmored military vehicle.

The transmission 400 includes a driver selectable range selection. Thetransaxle 450 contains a differential lock that is air actuated andcontrolled by switches on driver's control panel. Indicator switchesprovide shift position feedback and add to the diagnostic capabilitiesof the vehicle. Internal mechanical disconnects within the transaxle 450allow the vehicle to be either flat towed or front/rear lift and towedwithout removing the drive shafts. Mechanical air solenoid over-ridesare easily accessible at the rear of the vehicle. Once actuated, nofurther vehicle preparation is needed. After the recovery operation iscomplete, the drive train is re-engaged by returning the air solenoidmechanical over-rides to the original positions.

The transaxle 450 is designed to reduce the weight of the militaryvehicle 1000. The weight of the transaxle 450 was minimized byintegrating the transfercase and rear differential into a single unit,selecting an optimized gear configuration, and utilizing high strengthstructural aluminum housings. By integrating the transfercase and reardifferential into transaxle 450 thereby forming a singular unit, theconnecting drive shaft and end yokes traditionally utilized between toconnect them has been eliminated. Further, since the transfercase andrear carrier have a common oil sump and lubrication system, the oilvolume is minimized and a single service point is used. The gearconfiguration selected minimizes overall dimensions and mass providing apower dense design. The housings are cast from high strength structuralaluminum alloys and are designed to support both the internal drivetrain loads as well as structural loads from the suspension system 460and frame, eliminating the traditional cross member for added weightsavings. According to the exemplary embodiment shown in FIG. 10A, atleast a portion of the suspension system 460 (e.g., the upper controlarm 462, the lower control arm 464, both the upper and lower controlarms 462, 464, a portion of the spring 466, damper 468, etc.) is coupledto the transaxle 450. Such coupling facilitates assembly of militaryvehicle 1000 (e.g., allowing for independent assembly of the rear axle)and reduces the weight of military vehicle 1000. The front axle gearboxalso utilizes weight optimized gearing, aluminum housings, and acts as astructural component supporting internal drive train, structural, andengine loads as well. The integrated transfercase allows for a modularaxle design, which provides axles that may be assembled and then mountedto the military vehicle 1000 as a single unit. An integral neutral andfront axle disconnect allows the military vehicle 1000 to be flat towedor front/rear lift and towed with minimal preparation. Further, theintegrated design of the transaxle 450 reduces the overall weight of themilitary vehicle 1000. The transaxle 450 further includes a disconnectcapability that allows the front tire assemblies 600 to turn withoutrotating the entire transaxle 450. Housings of the front and reargearbox assembly are integrated structural components machined, forexample, from high strength aluminum castings. Both front and reargearbox housings provide stiffness and support for rear module 130 andthe components of the suspension system 460.

Suspension

The military vehicle 1000 includes a suspension system 460. Thesuspension system 460 includes high-pressure nitrogen gas springs 466calibrated to operate in tandem with standard low-risk hydraulic shockabsorbers 468, according to an exemplary embodiment. In one embodiment,the gas springs 466 include a rugged steel housing with aluminum endmounts and a steel rod. The gas springs 466 incorporate internal sensorsto monitor a ride height of the military vehicle 1000 and providefeedback for a High Pressure Gas (HPG) suspension control system. Thegas springs 466 and HPG suspension control system are completely sealedand require no nitrogen replenishment for general operation.

The HPG suspension control system adjusts the suspension ride heightwhen load is added to or removed from the military vehicle 1000. Thecontrol system includes a high pressure, hydraulically-actuated gasdiaphragm pump, a series of solenoid operated nitrogen gas distributionvalves, a central nitrogen reservoir, a check valve arrangement and amultiplexed, integrated control and diagnostics system.

The HPG suspension control system shuttles nitrogen between eachindividual gas spring and the central reservoir when the operator altersride height. The HPG suspension control system targets both the propersuspension height, as well as the proper gas spring pressure to prevent“cross-jacking” of the suspension and ensure a nearly equal distributionof the load from side to side. The gas diaphragm pump compressesnitrogen gas. The gas diaphragm pump uses a lightweight aluminum housingand standard hydraulic spool valve, unlike more common larger iron castindustrial stationary systems not suitable for mobile applications.

The suspension system 460 includes shock absorbers 468. In addition totheir typical damping function, the shock absorbers 468 have a uniquecross-plumbed feature configured to provide auxiliary body roll controlwithout the weight impact of a traditional anti-sway bar arrangement.The shock absorbers 468 may include an equal area damper, a positiondependent damper, and/or a load dependent damper.

Brakes

The braking system 700 includes a brake rotor and a brake caliper. Thereis a rotor and caliper on each wheel end of the military vehicle 1000,according to an exemplary embodiment. According to an exemplaryembodiment, the brake system includes an air over hydraulic arrangement.As the operator presses the brake pedal, and thereby operates a treadlevalve, the air system portion of the brakes is activated and applies airpressure to the hydraulic intensifiers. According to an exemplaryembodiment, military vehicle 1000 includes four hydraulic intensifiers,one on each brake caliper. The intensifier is actuated by the air systemof military vehicle 1000 and converts air pressure from onboard militaryvehicle 1000 into hydraulic pressure for the caliper of each wheel. Thebrake calipers are fully-integrated units configured to provide bothservice brake functionality and parking brake functionality.

To reduce overall system cost and weight while increasing stoppingcapability and parking abilities, the brake calipers may incorporate aSpring Applied, Hydraulic Released (SAHR) parking function. The parkingbrake functionality of the caliper is created using the same frictionalsurface as the service brake, however the mechanism that creates theforce is different. The calipers include springs that apply clampingforce to the brake rotor to hold the military vehicle 1000 stationary(e.g. parking). In order to release the parking brakes, the brakingsystem 700 applies a hydraulic force to compress the springs, whichreleases the clamping force. The hydraulic force to release the parkingbrakes comes through a secondary hydraulic circuit from the servicebrake hydraulic supply, and a switch on the dash actuates that force,similar to airbrake systems.

Referring specifically to the exemplary embodiment shown in FIG. 11,braking system 700 is shown schematically to include a motor 710 havinga motor inlet 712. The motor 710 is an air motor configured to be drivenby an air system of military vehicle 1000, according to an exemplaryembodiment. The motor 710 may be coupled to the air system of militaryvehicle 1000 with a line 714. As shown in FIG. 11, braking system 700includes a pump 720 that includes a pump inlet 722, a pump outlet 724,and a pump input shaft 726. The pump input shaft 726 is rotatablycoupled to the motor 710 (e.g., an output shaft of the motor 710).

As shown in FIG. 11, braking system 700 includes a plurality ofactuators 730 coupled to the pump outlet 724. According to an exemplaryembodiment, the actuators 730 includes a housing 732 that defines aninner volume and a piston 734 slidably coupled to the housing 732 andseparating the inner volume into a first chamber and a second chamber.The plurality of actuators 730 each include a resilient member (e.g.,spring, air chamber, etc.), shown as resilient member 736 coupled to thehousing and configured to generate a biasing force (e.g., due tocompression of the resilient member 736, etc.). According to anexemplary embodiment, the plurality of actuators 730 each also include arod 738 extending through an end of the housing 732. The rod 738 iscoupled at a first end to piston 734 and coupled at a second end to abrake that engages a braking member (e.g., disk, drum, etc.), shown asbraking member 740. As shown in FIG. 11, the rod is configured to applythe biasing force to the braking member 740 that is coupled to wheel andtire assemblies 600 thereby inhibiting movement of the military vehicle1000.

According to an exemplary embodiment, a control is actuated by theoperator, which opens a valve to provide air along the line 714.Pressurized air (e.g., from the air system of military vehicle 1000,etc.) drives motor 710, which engages pump 720 to flow a working fluid(e.g., hydraulic fluid) a through line 750 that couples the pump outlet724 to the plurality of actuators 730. According to an exemplaryembodiment, the pump 720 is a hydraulic pump and the actuator 730 is ahydraulic cylinder. Engagement of the pump 720 provides fluid flowthrough line 750 and into at least one of the first chamber and thesecond chamber of the plurality of actuators 730 to overcome the biasingforce of resilient member 736 with a release force. The release force isrelated to the pressure of the fluid provided by pump 720 and the areaof the piston 734. Overcoming the biasing force releases the brakethereby allowing movement of military vehicle 1000.

As shown in FIG. 11, braking system 700 includes a valve, shown asdirectional control valve 760, positioned along the line 750. Accordingto an exemplary embodiment, directional control valve 760 includes avalve body 770. The valve body 770 defines a first port 772, a secondport 774, and a reservoir port 776, according to an exemplaryembodiment. When valve gate 762 is in the first position (e.g.,pressurized air is not applied to air pilot 766) valve gate 762 placesfirst port 772 in fluid communication with reservoir port 776. Areservoir 780 is coupled to the reservoir port 776 with a line 752. Thereservoir 780 is also coupled to the pump inlet 722 with a line 754. Itshould be understood that the fluid may be forced into reservoir 780from any number of a plurality of actuators 730 by resilient member 736(e.g., when pump 720 is no longer engaged).

According to an exemplary embodiment, the directional control valve 760selectively couples the plurality of actuators 730 to the pump outlet724 or reservoir 780. The directional control valve 760 includes a valvegate 762 that is moveable between a first position and a secondposition. According to an exemplary embodiment, the valve gate 762 is atleast one of a spool and a poppet. The valve gate 762 is biased into afirst position by a valve resilient member 764. According to anexemplary embodiment, the directional control valve 760 also includes anair pilot 766 positioned at a pilot end of the valve gate 762. The airpilot 766 is coupled to line 714 with a pilot line 756. Pressurized airis applied to line 714 drives motor 710 and is transmitted to air pilot766 to overcome the biasing force of valve resilient member 764 andslide valve gate 762 into a second position. In the second position,valve gate 762 places first port 772 in fluid communication with 774thereby allowing pressurized fluid from pump 720 to flow into actuators730 to overcome the biasing force of resilient member 736 and allowuninhibited movement of military vehicle 1000.

Control System

Referring to FIG. 12, the systems of the military vehicle 1000 arecontrolled and monitored by a control system 1200. The control system1200 integrates and consolidates information from various vehiclesubsystems and displays this information through a user interface 1201so the operator/crew can monitor component effectiveness and control theoverall system. For example, the subsystems of the military vehicle 1000that can be controlled or monitored by the control system 1200 are theengine 300, the transmission 400, the transaxle 450, the suspensionsystem 460, the wheels and tire assemblies 600, the braking system 700,the fuel system 800, the power generation system 900, and a trailer1100. However, the control system 1200 is not limited to controlling ormonitoring the subsystems mentioned above. A distributed controlarchitecture of the military vehicle 1000 enables the control system1200 process.

In one embodiment, the control system 1200 provides control for terrainand load settings. For example, the control system 1200 canautomatically set driveline locks based on the terrain setting, and canadjust tire pressures to optimal pressures based on speed and load. Thecontrol system 1200 can also provide the status for the subsystems ofthe military vehicle 1000 through the user interface 1201. In anotherexample, the control system 1200 can also control the suspension system460 to allow the operator to select appropriate ride height.

The control system 1200 may also provide in-depth monitoring and status.For example, the control system 1200 may indicate on-board power, outputpower details, energy status, generator status, battery health, andcircuit protection. This allows the crew to conduct automated checks onthe subsystems without manually taking levels or leaving the safety ofthe military vehicle 1000.

The control system 1200 may also diagnose problems with the subsystemsand provide a first level of troubleshooting. Thus, troubleshooting canbe initiated without the crew having to connect external tools or leavethe safety of the military vehicle 1000.

The construction and arrangements of the vehicle, as shown in thevarious exemplary embodiments, are illustrative only. Although only afew embodiments have been described in detail in this disclosure, manymodifications are possible (e.g., variations in sizes, dimensions,structures, shapes and proportions of the various elements, values ofparameters, mounting arrangements, use of materials, colors,orientations, etc.) without materially departing from the novelteachings and advantages of the subject matter described herein. Someelements shown as integrally formed may be constructed of multiple partsor elements, the position of elements may be reversed or otherwisevaried, and the nature or number of discrete elements or positions maybe altered or varied. The order or sequence of any process, logicalalgorithm, or method steps may be varied or re-sequenced according toalternative embodiments. Other substitutions, modifications, changes,and omissions may also be made in the design, operating conditions andarrangement of the various exemplary embodiments without departing fromthe scope of the present invention.

1. A military vehicle comprising: a chassis; an axle coupled to thechassis a tractive element coupled to the axle; a brake positioned tofacilitate braking the tractive element; a brake housing defining aninner volume; a piston separating the inner volume into a first chamberand a second chamber; a rod extending through an end of the brakehousing and coupled to the piston, the rod positioned to selectivelyengage with the brake to inhibit movement of the tractive element; aresilient member positioned within the inner volume and configured togenerate a brake biasing force against the piston such that the rod isbiased into engagement with the brake; and an air-to-hydraulicintensifier coupled to the brake housing, the air-to-hydraulicintensifier configured to receive a supply of air and provide ahydraulic fluid to the brake housing based on the supply of air toovercome the brake biasing force to disengage the rod from the brake topermit movement of the tractive element.
 2. The military vehicle ofclaim 1, wherein the air-to-hydraulic intensifier includes a hydraulicpump.
 3. The military vehicle of claim 1, further comprising: a valvepositioned between the air-to-hydraulic intensifier and the brakehousing; and a hydraulic reservoir fluidly coupled to the valve and theair-to-hydraulic intensifier.
 4. The military vehicle of claim 3,wherein the valve includes a first port fluidly coupled to theair-to-hydraulic intensifier, a second port fluidly coupled to thehydraulic reservoir, and a third port fluidly coupled to the brakehousing.
 5. The military vehicle of claim 4, wherein the valve includesa valve gate that is repositionable between a first position and asecond position, the first position coupling the first port to the thirdport to fluidly couple the air-to-hydraulic intensifier to the brakehousing, the second position coupling the second port to the third portto fluidly couple the hydraulic reservoir to the brake housing.
 6. Themilitary vehicle of claim 5, wherein the valve includes: an air pilotpositioned at a first end of the valve gate; and a biasing elementpositioned at an opposing second end of the valve gate, the biasingelement configured to provide a valve biasing force to the valve gate tobias the valve gate into the second position.
 7. The military vehicle ofclaim 6, wherein the brake biasing force of the resilient member isconfigured to bias the piston to force the hydraulic fluid out of thebrake housing, through the valve, and into the hydraulic reservoir inresponse to the valve being in the second position.
 8. The militaryvehicle of claim 6, further comprising an air supply line coupled to theair-to-hydraulic intensifier and the air pilot, the air supply lineconfigured to provide the supply of air to the air-to-hydraulicintensifier and the air pilot.
 9. The military vehicle of claim 8,wherein the supply of air provided to the air pilot overcomes the valvebiasing force to reposition the valve gate into the first position toplace the air-to-hydraulic intensifier into fluid communication with thebrake housing to facilitate disengaging the brake.
 10. A brake systemcomprising: a brake configured to facilitate braking a tractive element;a brake housing defining an inner volume; a piston separating the innervolume into a first chamber and a second chamber; a rod extendingthrough an end of the brake housing and coupled to the piston, the rodpositioned to selectively engage with the brake to inhibit movement ofthe tractive element; a resilient member positioned within the innervolume and configured to generate a brake biasing force against thepiston such that the rod is biased into engagement with the brake; andan air-to-hydraulic intensifier coupled to the brake housing, theair-to-hydraulic intensifier configured to receive a supply of air andprovide a hydraulic fluid to the brake housing based on the supply ofair to overcome the brake biasing force to disengage the rod from thebrake to permit movement of the tractive element.
 11. The brake systemof claim 10, wherein the air-to-hydraulic intensifier includes ahydraulic pump.
 12. The brake system of claim 10, further comprising: avalve positioned between the air-to-hydraulic intensifier and the brakehousing; and a hydraulic reservoir fluidly coupled to the valve and theair-to-hydraulic intensifier.
 13. The brake system of claim 12, whereinthe valve includes a first port fluidly coupled to the air-to-hydraulicintensifier, a second port fluidly coupled to the hydraulic reservoir,and a third port fluidly coupled to the brake housing.
 14. The brakesystem of claim 13, wherein the valve includes a valve gate that isrepositionable between a first position and a second position, the firstposition coupling the first port to the third port to fluidly couple theair-to-hydraulic intensifier to the brake housing, the second positioncoupling the second port to the third port to fluidly couple thehydraulic reservoir to the brake housing.
 15. The brake system of claim14, wherein the valve includes: an air pilot positioned at a first endof the valve gate; and a biasing element positioned at an opposingsecond end of the valve gate, the biasing element configured to providea valve biasing force to the valve gate to bias the valve gate into thesecond position.
 16. The brake system of claim 15, wherein the brakebiasing force of the resilient member is configured to bias the pistonto force the hydraulic fluid out of the brake housing, through thevalve, and into the hydraulic reservoir in response to the valve beingin the second position.
 17. The brake system of claim 15, furthercomprising an air supply line coupled to the air-to-hydraulicintensifier and the air pilot, the air supply line configured to providethe supply of air to the air-to-hydraulic intensifier and the air pilot.18. The brake system of claim 17, wherein the supply of air provided tothe air pilot overcomes the valve biasing force to reposition the valvegate into the first position to place the air-to-hydraulic intensifierinto fluid communication with the brake housing to facilitatedisengaging the brake.
 19. A military vehicle comprising: a brakeconfigured to facilitate braking a tractive element; a brake housingdefining an inner volume; a piston separating the inner volume into afirst chamber and a second chamber; a rod extending through an end ofthe brake housing and coupled to the piston, the rod positioned toselectively engage with the brake to inhibit movement of the tractiveelement; a resilient member positioned within the inner volume andconfigured to generate a brake biasing force against the piston to biasthe rod into engagement with the brake; a hydraulic reservoir; anair-to-hydraulic intensifier coupled to the brake housing, theair-to-hydraulic intensifier configured to receive a supply of air andprovide a hydraulic fluid to the brake housing based on the supply ofair to overcome the brake biasing force to disengage the rod from thebrake to permit movement of the tractive element; a valve including: afirst port fluidly coupled to the air-to-hydraulic intensifier; a secondport fluidly coupled to the hydraulic reservoir; a third port fluidlycoupled to the brake housing; a valve gate that is repositionablebetween a first position and a second position, the first positioncoupling the first port to the third port to fluidly couple theair-to-hydraulic intensifier to the brake housing, the second positioncoupling the second port to the third port to fluidly couple thehydraulic reservoir to the brake housing; an air pilot; and a biasingelement configured to provide a valve biasing force to the valve gate tobias the valve gate into the second position; and an air supply lineconfigured to provide the supply of air to the air-to-hydraulicintensifier and the air pilot; wherein the brake biasing force of theresilient member is configured to bias the piston to force the hydraulicfluid out of the brake housing, through the valve, and into thehydraulic reservoir in response to the valve being in the secondposition.
 20. The military vehicle of claim 19, wherein the supply ofair provided to the air pilot overcomes the valve biasing force toreposition the valve gate into the first position to place theair-to-hydraulic intensifier into fluid communication with the brakehousing to facilitate disengaging the brake.